PTOptimizer
PTOptimizer was originally created by Helmut Dersch as part of Panorama Tools, it is a simple wrapper program around optimization routines present in the pano12 library.
Source code for the original PTOptimizer was never released, however reconstruction was quite straightforward and a multi-platform version is now included with the pano12 library available at Sourceforge.
The updated original example script with lots of comments is found at Jim Watter's page